A wide variety of types of structures for disposable absorbent articles used to collect body fluids are known in the art. Commercially available absorbent articles include pad type articles such as sanitary napkins, panty liners, and adult incontinence products. Typically such articles include a liquid pervious topsheet, an absorbent core, a liquid impervious backsheet, and some type of fastener. The fastener often comprises a pressure sensitive adhesive fastener situated on the garment side of the article. The fastener is used for attaching the absorbent article to the crotch region of an undergarment (such as the wearer's panties in the case of a sanitary napkin). The pressure sensitive adhesive fastener is generally covered with a cover strip (or releasable strip) to prevent the adhesive from unintentionally sticking to surfaces other than the wearer's undergarment prior to use.
Absorbent articles having a profiled shape have regions of different caliper that are typically in their absorbent core. Generally, such absorbent articles are thicker in the center than at the ends. These profiled absorbent articles present special problems for attachment of a pressure sensitive adhesive fastener to the garment side of the article during manufacture. The problems become serious when the caliper differences from the leading edge of the core to the center of the core and from center of the core to the trailing edge are so large that it is difficult to supply sufficient pressure over the entire core to adhere the pressure sensitive adhesive fastener properly to the absorbent article.
If the pressure sensitive adhesive is not adhered properly to the garment surface of the absorbent article, when the release paper is peeled off, the adhesive will either be removed from the garment side of the absorbent article with the release paper, or even worse, will stay in the wearer's undergarment when the absorbent article is removed from the undergarment. This problem was previously solved by imparting such high pressures to adhere the fastener to the garment side of the absorbent article so as to risk damaging the absorbent core of the article.
As a result, a need exists for an improved method and apparatus for attaching a fastener to a profiled absorbent article. It is, therefore, an objection of the present invention to provide a method and apparatus for attaching a pressure sensitive fastener to a profiled absorbent article which adequately adheres the fastener to the garment side of the absorbent article without using pressures which are so great that the absorbent article is damaged.
This and other objects of the present invention will be more readily apparent when considered in reference to the following description and when taken in conjunction with the accompanying drawings.